Various combinations of springs and shock absorbers are known to absorb the landing energy of aircraft and provide suspension. Electric, hydraulic, or pneumatic systems have been used to extend and retract the gear, in some cases using the shock absorbing cylinder as an actuator. Most prior shock absorbing systems have the characteristic that high forces associated with hard or crash landings will structurally fail the shock absorbers before any significant energy is absorbed, so the structure and passengers absorb all crash forces. Other prior systems absorb crash forces by permanently deforming a portion of the shock absorbing device.
A primary object of the invention therefore is to provide a combined suspension and shock absorber having a simple pressure limiting means that operates during hard or crash landings, such that maximum impact energy is absorbed before the shock absorber bottoms or fails.
A further object of the invention is to provide such a suspension and shock absorber which is also operable as an actuator for a retractable landing gear.
A further object is to provide a retractable landing gear actuator as above which can be powered with low pressure air or other gas.
The above as well as additional objects, features, and advantages of the invention will become apparent in the following detailed description.